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Hop-by-hop Content Distribution with Network Coding in Multihop Wireless Networks

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Digital Communications and Networks 2017年第1期3卷 47-54页

作者： Rami Halloush Hang Liu lijun Dong mingquan Wu Hayder Radha Department of Telecommunications Engineering Yarmouk University Irbid Jordan Department of Electrical Engineering and Cor~uter Sci The Catholic University of America Washington DC USA Huawei Research Center Santa Clara CA USA Huawei Technologies USA Inc. Bridgewater N J USA Department of Electrical and Computer Engineering Michigan State University East Lansing MI USA

The predominant use of today＇s networks is content access and distribution. Network Coding （NC） is an innovative technique that has potential to improve the efficiency of multicast content distribution over multihop Wireless Mesh Networks （WMNs） by allowing intermediate Forwarding Nodes （FNs） to encode and then forward data packets. Practical protocols are needed to realize the benefits of the NC technique. However, the existing NC-based multicast protocols cannot accurately determine the minimum number of coded packets that a FN should send in order to ensure successful data delivery to the destinations, so that many redundant packets are injected into the network, leading to performance degradation. In this paper, we propose HopCaster, a novel reliable multicast protocol that incorporates network coding with hop-by-hop transport. HopCaster completely eliminates the need for estimating the number of coded packets to be transmitted by a FN, and avoids redundant packet transmissions. It also effectively addresses the challenges of heterogeneous mulficast receivers. Moreover, a cross-layer multicast rate adaptation mechanism is proposed, which enables HopCaster to optimize multicast throughput by dynamically adjusting wireless transmission rate based on the changes in the receiver population and channel conditions during the course of mulficasting a coded data chunk. Our evaluations show that HopCaster significantly outperforms the existing NC-based multicast protocols.

关键词： Content distributionNetwork coding MulticastHop-by-hop transportRate adaptation

底部气流对CO_2激光切割硅钢切口质量的影响

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光学学报 2008年第3期28卷 522-527页

作者：洪蕾米承龙李力钧上海海事大学机械系上海 200135 湖南大学机械系湖南长沙 410082

激光切割相对冲压及线切割工艺具有自由度大、加工效率高、不会影响铁心质量等优点,但由于残渣及切口粗糙问题一定程度上影响了激光切割硅钢片的质量和应用范围。通过采用在工件底部增设辅助侧吹喷嘴,控制熔渣流向,保证成品切割质量激... 详细信息

激光切割相对冲压及线切割工艺具有自由度大、加工效率高、不会影响铁心质量等优点,但由于残渣及切口粗糙问题一定程度上影响了激光切割硅钢片的质量和应用范围。通过采用在工件底部增设辅助侧吹喷嘴,控制熔渣流向,保证成品切割质量激光切割工艺,试验证明,合理控制工艺参量,可获得良好效果。利用有限元法进一步对工件底部气流状况进行了数值模拟,分析了流动过程中在不同的角度和流速下光斑移动和气流场变化的情况,初步确定工件底部侧吹气流以20°吹入的辅助侧吹工艺,为进一步合理控制熔渣流向获得光滑的精细切口提供了实践和理论依据。

关键词：激光技术氧助激光切割侧吹气流硅钢片熔渣

Peptidoglycan inhibits beigeing of adipose tissue

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Acta Pharmaceutica Sinica B 2022年第2期12卷 990-993页

作者： Hong Chen lijun Sun Lu Feng michael Mulholland Weizhen Zhang Yue Yin Department of Physiology and Pathophysiology School of Basic Medical SciencesKey Laboratory of Molecular Cardiovascular ScienceMinistry of EducationPeking UniversityBeijing 100191China Department of Surgery University of Michigan Medical CenterAnn ArborMI 48109-0346USA

To the Editor:Obesity, an epidemic metabolic disease characterized by excessive fat accumulation, causes a significant economic burden on families and the society. The discovery of beige adipocytes has provided us with a brand new approach for the intervention of obesity^(1). Beige adipocytes increase energy expenditure and improve the balance of glucose and lipid metabolism. Reduction of beige adipocytes is a hallmark of obesity. Mechanism underlying the decrement of beigeing remains largely unknown.

关键词： Beige adipocytes Brown adipocytes Obesity Metabolic inflammation

Surface Tension Calculation of Undercooled Alloys

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Rare Metals 2001年第1期20卷 58-61页

作者： Zhiyu Qiao, lijun Yan, Zhanmin Cao, Guirong Liu (Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China) Univ Sci & Technol Beijing Dept Phys Chem Beijing 100083 Peoples R China

Based on the Butler equation and extrapolated thermodynamic data of undercooled alloys from those of liquid stable alloys, a method for surface tension calculation of undercooled alloys is proposed. The surface tensions of liquid stable and undercooled Ni-Cu (x(Ni)=0.42) and Ni-Fe (x(Ni)=0.3 and 0.7) alloys are calculated using STCBE (Surface Tension Calculation based on Butler Equation) program. The agreement between calculated values and experimental data is good enough, and the temperature dependence of the surface tension can be reasonable down to 150-200 K under the liquid temperature of the alloys.

关键词： undercooled alloy surface tension Butler equation

论著肥胖和消瘦儿童间生活行为对FAIM2启动子甲基化的影响：人群研究

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英国医学杂志中文版 2015年第8期18卷 438-446页

作者： Wu, lijun Zhao, Xiaoyuan Huang, Guimin Zhang, Meixian Yinkun Yan Hou, Dongqing Meng, Linghui Liu, Junting Cheng, Hong mi, Jie Shen, Yue Department of Epidemiology Capital Institute of Pediatrics Beijing China National Research Institute for Family Planning Beijing China

目标肥胖相关基因Fas细胞凋亡抑制分子2（FAIM2）可以被营养状况调控，并且其启动子甲基化水平与肥胖显著相关。生活行为因素，如静态生活行为和运动，可以修饰与肥胖相关的表观遗传状态。但是，FAIM2影响肥胖的分子机制是否与生活行为... 详细信息

目标肥胖相关基因Fas细胞凋亡抑制分子2（FAIM2）可以被营养状况调控，并且其启动子甲基化水平与肥胖显著相关。生活行为因素，如静态生活行为和运动，可以修饰与肥胖相关的表观遗传状态。但是，FAIM2影响肥胖的分子机制是否与生活行为相关还不清楚。本研究检测了肥胖和消瘦儿童间FAIM2启动子甲基化水平与静态生活行为和运动的潜在差异。

关键词：队列研究生活方式甲基化启动子儿童肥胖

Trends and perspectives on general Pesticide analytical chemistry

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Advanced Agrochem

Advanced Agrochem 2022年第2期1卷 113-124页

作者： Yangliu Wu lijun Han Xuemin Wu Wayne Jiang Hui Liao Zhi Xu Canping Pan Innovation Center of Pesticide Research Department of Applied ChemistryCollege of ScienceChina Agricultural UniversityBeijing100193China Key Laboratory of National Forestry and Grassland Administration on Pest Chemical Control China Agricultural UniversityBeijing100193China Department of Entomology Michigan State UniversityEast LansingMI48824USA Safety and Quality Institute of Agricultural Products Heilongjiang Academy of Agricultural SciencesThe Ministry of Agriculture of Agricultural Products Quality Safety Risk Assessment LaboratoryHarbin150086China Key Laboratory of Quality and Safety Control for Subtropical Fruit and Vegetable Ministry of Agriculture and Rural AffairsHainan571101China

Agrochemicals are indispensable materials in agricultural production,used to control or prevent diseases,insects and weeds,and play important roles in ensuring both food security and food ***,the negative impacts of modern synthetic pesticides on humans and the environment could not be ***,the production,registration,application and monitoring of pesticides should be strictly checked to ensure their commercial product quality and safety to human health as well as to the *** review summarizes the analytical chemistry involved in the quality control(QC)analysis for commercial formulation,residue analysis,dietary risk assessment and regulation prospects of *** main concepts and contents of pesticide analytical chemistry are comprehensively introduced and *** addition,the requirements and criteria of the relevant guidelines from various organizations are ***,the research frontier areas and future trending for the invention of new generation of agrochemicals,registration/enforcement,market monitoring and risk management of pesticides are discussed.

关键词： Pesticide Formulation analysis Residue analysis Review

Overexpression of inhibinα(1-32)fusion protein promotes apoptosis and cell cycle arrest in a cervical cancer cell model(Hela cells)

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BIOCELL 2014年第1期38卷 17-24页

作者： Yanhong ZHEN Li HAN Kailai CAI lijun HUO Hasan RIAZ Canjie WU Aixin LIANG Lei SANG Liguo YANG Key laboratory of Agricultural Animal Genetics Breeding and Reproduction of Ministry of Education.Huazhong Agricultural UniversityWuhan430070HubeiChina College of Animal Science and Veterinary Medicine Huazhong Agricultural UniversityWuhanHubei 430070China

Inhibins play important roles in the reproductive system. To evaluate whether inhibin α (1-32) fusion protein plays a role in cervical cancer growth, the plasmid pVAX-inhα was constructed and its effect on proliferation and apoptosis of the human cervical cancer cell line (Hela) was checked by flow cytometry and real-time PCR. The expression and localization of inhibin α protein were detected by RT-PCR and confocal mi- croscopy which showed that inhibin α protein was expressed and localized in the nucleus of Hela cells. Over ex- pression of inhibin α gene significantly induced cell apoptosis and ceased S phase of cell cycle. Furthermore, cell proliferation was significantly suppressed 96 h post-transfection and mRNA level of anti-apoptosis genes (Bcl-2, NFκB) were decreased but pro-apoptosis genes (Bax, wild type p53) and inhibin co receptor (TGFβR3) were increased, indicating that inhibin, through its co-receptor, might activate apoptotic and cell growth cascades which regulate proliferation and apoptosis in Hela cells. These results suggest that inhibin α (1-32) fusion pro- tein, located in the cell nucleus, can regulate Hela cells growth and apoptosis by induction of apoptotic pathways such as NFκB, Bcl-2 and p53 families. These findings may have a significant impact on future research regarding cervical cancer cell lines.

关键词： inhibinα(1-32) Hela cells proliferation apoptosis overexpression

Association between serum uric acid level and the severity of coronaryartery disease in patients with obstructive coronary artery disease

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Chinese Medical Journal 2014年第6期127卷 1039-1045页

作者： Jie Yu Jiangli Han Jieming Mao lijun Guo Wei Gao Department of Cardiology Peking University Third Hospital Beijing 100191 China Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing 100191 China. Department of Cardiology Peking University Third Hospital Beijing 100191 China Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides Ministry of Health and Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing 100191 China. Email: sister.han@***.

Background Many studies have shown that the serum uric acid(SUA) level is one of the cardiovascular risk factors. The aim of the study is to evaluate the relationship between SUA levels and the severity of coronary artery disease(CAD) assessed by angiography and the Syntax score in patients with obstructive *** Participants who visited our hospital for a coronary angiography, from December 2007 to September 2012, were eligible for this analysis. SUA and other blood parameters after at least 12-hour fast were determined. First, the patients were divided into tertiles according to their Syntax scores(low Syntax score group: Syntax score ≤10.0; moderate Syntax score group: 10.0 18.0). Second, to clarify the association between SUA levels and major adverse cardiovascular events(MACEs), all patients were divided into two subgroups on the basis of SUA levels. The cutoff value of SUA was defined by diagnostic criteria of hyperuricemia. Patients were separated into normal SUA group(n=251, with SUA mi) and recurrent percutaneous coronary intervention(re-PCI). Results A total of 347 patients were registered for the study. The SUA levels in the high Syntax score group were significantly higher than that of the moderate Syntax score group and the low Syntax score group((392.3±81.6) μmol/L vs.(329.9±71.0) μmol/L, P <0.001;(392.3±81.6) μmol/L vs.(311.4±64.7) μmol/L, P <0.001). The SUA level was positively correlated not only with the Syntax score(r=0.421, P <0.001; 95% CI: 0.333–0.512), but also with the number of diseased vessels(r=0.298, P <0.001; 95% CI: 0.19

关键词： serum uric acid obstructive coronary artery disease Syntax score

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垂直轴风力机叶片改进动态失速模型

中国机械工程 2019年第6期30卷 644-649,657页

作者：张立军赵昕辉马东辰米玉霞王旱祥姜浩中国石油大学(华东)机电工程学院青岛266580

为研究垂直轴风力机叶片在动态失速下的气动性能,结合风力机的实际工作情况对常用动态失速模型——B-L模型和miT模型进行了修正。以Sandia实验室17 m垂直轴风力机为例,计算了风力机叶尖速比分别为2.33和3.09时叶片的动态切向力系数和动... 详细信息

为研究垂直轴风力机叶片在动态失速下的气动性能,结合风力机的实际工作情况对常用动态失速模型——B-L模型和miT模型进行了修正。以Sandia实验室17 m垂直轴风力机为例,计算了风力机叶尖速比分别为2.33和3.09时叶片的动态切向力系数和动态法向力系数。研究结果显示:miT修正模型对风力机上风区的切向力系数和下风区的法向力系数的预测精度较高;B-L修正模型对风力机上风区的法向力系数和下风区的切向力系数的计算结果与实验数据较一致。

关键词：垂直轴风力机动态失速 B-L模型 miT模型双致动盘多流管